1. Field of the Invention
The present invention relates to a waveform observing apparatus.
2. Description of the Background Art
There has been used a waveform observing apparatus for observing a temperature and pressure of equipment on a factory production line. The apparatus historically used to be one for writing a waveform on rolled paper (chart), but with the development of electronic equipment, a waveform observing apparatus that displays a waveform by use of a display in place of paper is currently in wide use.
The waveform observing apparatus is capable of displaying in a display section a constantly varying measured value, namely a time-series waveform, while storing measured data captured from a thermocouple or the like into a memory mounted to the waveform observing apparatus. For example, Japanese Patent Application Laid-Open No. H7-114349 and Japanese Patent Application Laid-Open No. 2002-82133 each disclose a waveform observing apparatus having a display with a touch panel. Japanese Patent Application Laid-Open No. H7-114349 proposes that, by a user touching a function key displayed in a display section, a function designated by the function key displayed in the display section is executed. Japanese Patent Application Laid-Open No. 2002-82133 displays that, while a displayed waveform is observed, an operation of inputting a comment or a marking by pen-input is performed using a pen-input touch screen.
There has been a request as the need for the waveform observing apparatus to rapidly enlarge and reduce a displayed waveform even when the waveform observing apparatus repeatedly stops and starts collection of measured data, while leaving measured data before stoppage on the screen of the display section. In the case of responding to this first request, it is desired that, when collection of measured data is once stopped and then resumed, a boundary between the stoppage and the resuming be seen in a display on the screen. Naturally, the number of pieces of measured data storable in the waveform observing apparatus is finite, and hence it is not preferable to make a display including measured data having already been deleted.
An object of the present invention is to provide a waveform observing apparatus capable of facilitating management of compressed data and measured data which were created for a reduced display in making the reduced display, to facilitate deletion of compressed data corresponding to measured data at the time of deleting the measured data.
A further object of the present invention is to provide a waveform observing apparatus capable of reducing a calculating amount in making a reduced display so as to improve response to the reduced display.
A further object of the present invention is to provide a waveform observing apparatus capable of displaying a boundary between stoppage and start of collection of measured data in a visually observable manner when a reduced display is made.